An after-dinner speech given on November 9, 2016*, on Alex Lubotzky’s 60th birthday conference: 60 faces to Groups.

As we all realized waking up this morning, today is a historic day*. It is the dinner day for Alex 60th‘s birthday conference, and I am thrilled to say a few words about Alex and to Alex. First let me send my love and my wife Mazi’s love to Alex and Yardena and all the family. A 60th birthday is a somber event, especially so when the birthday boy is younger than you, so I will be serious and try to move you and bring tears to your eyes, rather than try to be funny and make you laugh. (This is a new experience for me.) I will leave the many funny stories I can tell about Alex to his 70th birthday. To be on the safe side I will write them down soon so not to forget them.

Early days

I don’t know how and when Alex and I first met. Perhaps it was in 1970 or 1971 when Ron Livne (at the time a high school student like me and Alex) invited me to Tel Aviv to their “math club”. I remember meeting Alex in his home in the late 70s when we were both soldiers and he worked on his thesis and on the beautiful paper merging many different ideas and techniques using the “Golod-Shafarevich” theorem, along with Euler’s theorem for solving a well known problem. The paper appeared in the top journal of mathematics, the “Annals of Mathematics”, a rare achievement.

In 1985 I joined the Hebrew University as a faculty member, and Alex was already a professor there. When I joined the department I was in awe of the extraordinary group of people, not only in terms of their mathematical achievements, but also when their scholarly nature, their personalities, activities and interests beyond math. This feeling paralyzed me and I hoped it would pass in a couple of months. It didn’t, and even today on the verge of retirement, this is still my feeling and it extends also to the amazing group of people we hired since.

Alex is a great mathematician

I should not tell you how extraordinarily great a mathematician Alex is, and the mathematicians here can describe Alex’s work better than I can. But to his family I want to mention a few “buzz words” reflecting some of Alex’s work: “Ramanujan graphs”, and “powerful groups,” “subgroup growth” and the “Tau property” and the “Sandwich technique” (juggling between Tao and Kazhdan’s T-poperty) , “high dimensional expanders” (I taught with Alex four times a course on this topic. At the end I may understand what it’s about) and many, many more concepts.

Alex is a great friend

both to his close friends and to people who are more distant. In many cases people enjoy listening to Alex’s life-wisdom (this was already the case when he was in his twenties, even when they were much older) and advice, and confide in him their most intimate experiences and dilemmas. In these cases, the friendship relations are not quite symmetric, can we characterize what they are? It is not like the relationship you have with a father. Usually you do not want to hear words of wisdom about life from a parent and you certainly don’t want to share your intimate matters with them. It is more like the relation you have with a loving… grandfather. So you can say that Alex’s form of friendship was an early practice for grandfatherhood. Alex practiced being a grandfather all his life and now he can use his skills with his 16 and counting grandchildren. Alex is a great champion of grandchildren and I suppose he is starting to pressure his children to have grandchildren of their own about now.

Alex is an idealist

This is why he and Yardena settled in Efrat, this is why he worked hard to save and advance the “Israel Journal of Mathematics”, and this is why he went into politics. Alex joined politics in 95 and the Israeli parliament after the 99 elections. (A major upset at the time. Commentators and polls predicted victory for one candidate but the other candidate won. This happens from time to time*.) I remember talking with Hillel about hosting a farewell party for Alex. Hillel was surprised that a mathematical genius like Alex would join the parliament and I thought he would never come back.

Alex’ many virtues and two weaknesses as a leader

Alex had a lot of virtues and two weaknesses as a leader and a politician. Alex was very smart and he could understand the fine details as well as the large picture. He befriended and connected well with other politicians from all parties. In politics and administration just like in mathematics, he could identify the important problems and he went head on to tackle them. He is famous for the Beilin-Lubotzky convention for relations between orthodox and non-orthodox Jews and many other related issues. One of his weaknesses is that he is not malicious and does not appreciate the joy of malice. As in mathematics, also in politics and in academic administration, he could identify the important problems and he went head on to tackle them. He was also the founder of the committee for the status of women in the Israeli parliament. [Here, in the lecture, Alex corrected me and said that I am exaggerating and he was not the founder. But I made the mistake on purpose to make another point.] … Right, Alex was an active member of this committee, not the founder. It was founded 4 years earlier by Yael Dayan (Moshe Dayan’s daughter). This brings me to the second weakness of Alex as a politician. He is too honest. Most politicians and also a few mathematicians will not correct an undeserved credit.

Parents

Alex comes from a family of holocaust survivors and to a large extent regards himself as one. In my impression this accounts primarily for his immense gratitude for what he was blessed with, including the sweet life of a mathematician. It is also related to a principle he has of never wasting food and never wasting time. We shared apartments quite a few times and he also refused to throw away food. (About Alex’s cooking wait 10 years.) Once I visited him and Yardena when they were renting a house filled with spoiled non kosher food that had been left by the owner and I secretly threw away most of it. A legacy from Alex’s father Issar is never to waste time. (I mean time when one is awake, this does not include sleeping, we already heard stories about Alex’s sacred afternoon sleep.) “A time being wasted is like a time being dead,” Alex once told me when he caught me playing a computer game at the computer room at Yale. (I wonder how this statement could be scientifically verified.) Since then I was careful to quickly move to a different screen when Alex entered the computer room.

You can read about the remarkable history of Alex’s parents in WW2 in Asael’s soon to be published second book.

Asael

And I want to conclude with mentioning Alex as a father to Asael, and how Alex and Yardena handles Asael’s grave injury in 2006. I remember Mazi and I had dinner with Alex and Yardena and Avi and Edna a day or two before Alex and Yardena got the news that Asael was injured and that was in critical condition. This was a terrible ordeal and a difficult struggle, mainly for Asael but also for his parents and the entire family. Asael, now a medical doctor as well as a researcher, wrote his first book about his experiences, and has recently been translated to English.

Let me send again love from Mazi, myself and my children to Alex, Yardena and the family and wish Alex many more years. I haven’t talked about many joint adventures from the Jordan river to the Amazonas. I promise to be funny ten years from now.

*At that day November 9, 2016, we woke up in the morning realizing that Donald Trump was the newly-elected President of the United States. Efim Zelmanov mentioned in his after dinner speech that Alex did not share the universal confidence that Trump will not be elected.